One of the sources which contribute to the loss of power and mass efficiency in compressor is the gas discharge system. In a gas discharge system in which the displacement of the one or more discharge valves is adjusted, that is, the discharge valve opens and closes in desired moments and with low oscillation, the mass efficiency is favored by eliminating or reducing the reflux, minimizing power loss due to the flow of gas through the valve.
The pressures upstream and downstream the discharge valve are some of the variables which define the operational dynamic thereof. Such variables depend on the refrigerant gas, on the operational condition of the compressor, on the design of the discharge orifice and, specially, on the construction of the discharge filter.
Improvements on the discharge filter and on the assembly defined by the discharge orifice and discharge valve, in order to reduce the restrictions imposed by said components, have a direct impact in the energy consumption and consequently in the efficiency of the compressor, particularly in the hermetic refrigeration compressors.
In the refrigeration compressors, the gas compressed by the displacement of the piston (driven by a connecting rod-crankshaft mechanism, or by a resonant spring in the linear compressor) is directly discharged in a discharge chamber usually defined in the interior of the cylinder cap. In these constructions, the gas reaching the discharge chamber undergoes a pressure reduction, spreading in a random and turbulent manner in the interior of the discharge chamber, in the valve plate region, which results in power loss.